The following is a tabulation of some prior art that presently appears relevant:
U.S. PatentsPatent NumberKind CodeIssue DatePatentee8,915,077B22014 Dec. 23Paakkinen8,887,501B22014 Nov. 18Paakkinen8,739,512B22014 Jun. 03Kanki8,614,521B22013 Dec. 24Babaritet al.8,456,026B22013 Jun. 04Cleveland8,269,365B22012 Sep. 18Clement et al.8,046,108B22011 Oct. 25Hench7,989,975B22011 Aug. 02Clement et al.7,934,773B22011 May 03Boulais et al.7,906,865B22011 Mar. 15Minguela et al.7,484,460B22009 Feb. 03Blum et al.7,453,165B22008 Nov. 18Hench7,375,436B12008 May 20Goldin7,003,947B22006 Feb. 26Kanki6,888,262B22005 May 03Blakemore6,876,095B22005 Apr. 05Williams6,095,9262000 Aug. 01Hettema et al.6,027,3422000 Feb. 22Brown4,843,2501989 Jun. 27Stupakis4,352,0231982 Sep. 28Sachs et al.4,266,1431981 May 05Ng3,577,6551971 May 04Pancoe3,231,7491966 Jan. 25Hinck  937,7121909 Oct. 19McFarlandU.S. Patent applicationsPatent NumberKind CodeIssue DateApplicant2015/0123406A12015 May 07Paakkinen2012/0001432A12012 Jan. 05Clement et al.2011/0012443A12011 Jan. 20PowersWO Patent applicationsPatent NumberKind CodeIssue DateApplicantWO2012103890A12012 Aug. 09Jan OlsenWO2010034888A12010 Apr. 01Paakkinen